Digital DTI datalogger

I had a digital DTI project on the go, and was using a complex mix of hardware to convert its serial data output to sane values, then spit it back through a serial>USB converter. This was a pain in the bum and meant I had to run that and a laptop to datalog it. Seeing as I also wanted to datalog a couple of other channels (voltage and current) this was going to require a separate input and tying them all together in the laptop. Ugh.

So I bought an Arduino Mega 2560 and an LCD touchscreen for it which came with an SD card slot. I’ve spent a little time writing the code to display all channels, allow turning on and off various IO via the touchscreen, and datalogging to the SD card. It’s working fairly well but I’m struggling to get the current resolution fine enough to capture down to the 50mA I need to measure. I may try a simple sense resistor rather than a hall effect probe. I’ll update the page soon.